Yes, the Reserves "gotcha" - at one stage I was told that to make myself more competitive I should consider joining the Reserves. Off I went to Recruiting, where I was told that I couldn't have two applications in The System at once, that I would have to effectively tear up my Pilot application, go into Reserves, start their training, then in 12 months or whatever re-start my application for pilot, as a serving member this time. I wouldn't have to do the aptitude test again, but would have to go through everything else, and then I was told "and you'll also have to apply for a release from Reserves, and they may not let you go".
So that was the end of that. Don't worry about a 3 month delay, you should get used to it actually! Use the time to go and join Boy Scouts as a leader or start a band or do a short TAFE course or do something else leadership oriented, don't just sit around and wait. They don't like that.